The disclosure of U.S. Ser. No. 08/234,681 is incorporated herein in its entirety. In that device, an automatic hub lock with manual override is provided for an existing spindle and axle. The axle is inserted through the cylindrical spindle. A drive gear is spline fit to the axle end which is protruded through the spindle and a lock ring secures the drive gear to the axle end. The drive gear's abutment to the spindle restricts movement of the axle back through the spindle. The drive gear includes exterior teeth or splines for engagement by a clutch ring that is also spline fit to the wheel hub. Engagement of the clutch ring to both the drive gear and wheel hub interlocks the wheel and axle in four-wheel drive.
There are numerous other components that must be assembled to the clutch ring and wheel hub, and these components are in large part assembled sequentially and in a time consuming manner. It is an objective of this invention to provide a hub lock assembly that can be largely pre-assembled and then mounted as a unit to the vehicle's axle, spindle and wheel hub.
A second part of the invention concerns the manual override. When manual locking is desired, a dial is rotated by hand. The dial is connected to a spring biased cage that carries the clutch ring. The spring strongly urges the clutch ring to a disconnected condition and turning of the dial to the interlock condition is thus strongly resisted and may be difficult for an operator to accomplish. It is accordingly a second objective of this invention to provide an assist to the operator for rotating the dial to the interlock position.